<!DOCTYPE html>
<html lang="zh-CN">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>子代选择器</title>
    <style>
      ul > li {
        border: 1px solid chartreuse;
      }
    </style>
  </head>
  <body>
    <ul>
      <li>Unordered item</li>
      <li>
        Unordered item
        <ol>
          <li>Item1</li>
          <li>Item2</li>
        </ol>
      </li>
    </ul>
  </body>
</html>
